Synonyms for impenetrable | impenetrable synonyms

impassable (adjective)

Synonyms:

impassible.

impregnable (adjective)

Synonyms:

unassailable, inaccessible.

impermeable (noun)

dense (adjective)

Synonyms:

tight.

impervious (adjective)

inscrutable (adjective)

Synonyms:

incomprehensible, inconceivable.

unfathomable (noun)

trackless, insurmountable, mysterious,